CAPITOL HILL: Three top House Republicans want the Navy to come clean on just what ships it is counting as part of the nation’s fleet and why.

In what is clearly becoming a campaign issue for the GOP — witness last week’s Wall Street Journal by John Lehman, former Navy Secretary and Romney defense advisor — the chairmen of the House Armed Services seapower and projections forces, readiness and oversight and investigations subcommittees have written Navy Secretary Ray Mabus asking for a clear explanation of what constitutes the Battle Fleet.

They say they are “concerned” that the service is engaged “in an effort to exhibit to the public a larger fleet than actually exists.” In particular, Reps. Todd Akin, Randy Forbes and Robb Wittman want to know if the Navy is counting Patrol Coastal or hospital ships as part of the pointy end of the service.

Ever since it became clear that the Navy had to scale back the fleet from 313, the GOP has questioned the Navy’s plans, especially in light of the administration’s strategic tilt toward the Asia-Pacific region.

One of the really interesting issues is likely to become how will the problems that continue to plague the Littoral Combat Ship — which will constitute a large part of the Navy fleet in terms of numbers — will affect this debate. And those problems don’t even take into account the basic debate about whether LCS qualifies as a warship.

We look forward to the Pentagon’s speedy response to this letter.